A humpback whale "spy hops" near Petermann Island in the Western Antarctic Peninsula on March 18, 2016. The term spy hopping refers to moments when a whale surges vertically out of the water in order to get a better look at what is above the surface. It also occurs when whales are very active with one another. Photograph by Carolyn Van Houten

This Is What Whale Breath Smells Like

He kneels at the front of the Zodiac, aiming his crossbow at a humpback whale lazing at the water surface’s 20 feet away. He squeezes the trigger and the dart flies—just over the whale’s back.

“Sh**,” Ari Friedlaender says, “I shouldn’t have tried to do a skip shot.” He had hoped to bounce the dart off the water and hit the whale with a little less force, but now the animal disappears beneath the waves, as if annoyed by the buzzing of a mere insect.

Friedlaender calls into his handheld radio, speaking to the other boat: “Let’s look for that hooked dorsal with barnacles,” referring to a whale that he and the others have had their eye on.

It’s early afternoon on the western edge of the Antarctic Peninsula. Our two Zodiacs rise and fall in a gentle ocean swell, in sight of a row of dark, jagged peaks. The mountains are swaddled in glaciers that sweep down their slopes before ending in a row of ice cliffs along the water line.

A Whale of a Target

Friedlaender, a whale biologist from Oregon State University, is hoping to collect scientific biopsies of humpbacks—hence, the crossbow. We’re midway through a two-week cruise along the peninsula, during which he and a group of researchers are studying the health, behavior, and migrations of whales in one of the southernmost summer feeding grounds on Earth.

In a second boat 50 yards away are Lars Bejder, a whale biologist from Murdoch University in Perth, Australia, and Fredrik Christiansen, a postdoctoral fellow also from Murdoch. They’re using an aerial drone to unobtrusively photograph the same whales in order to estimate their size, body weight, and how much blubber they’ve stored away while feeding down here.

Half a dozen whales bob up and down in the water, the long, dark crests of their backs and dorsal fins in plain sight as they loll just below the surface. Fix your eyes on one of these whales and you see it take three or four breaths—powerful spurts of mist out the blowhole—then dive down for several minutes before surfacing, breathing again, and repeating the cycle. Each dive is probably taking them several hundred feet below the waves to lunge, open-mouthed, through a swarm of shrimpy little animals called krill.

The quadcopter drone buzzes 50 feet overhead; Christiansen controls it with a console, maneuvering to photograph a whale or two before he has to land the craft and change its battery.

For Friedlaender, today’s scenario is a bit more challenging. Retrieving a biopsy from a feeding whale requires a bit of social engineering. Because the whale only stays up long enough to take several breaths, Friedlaender has to guide the boat to it quickly—but not too quickly, or else it senses it’s being followed. He tries, instead, to steer the boat on a nonchalant course that will intersect with where he thinks the whale will be in a few seconds.

We approach a newly surfaced whale as it lets loose a whooshing blow of mist, then a second blow. We come closer. A third blow. Friedlaender raises the crossbow. We’re close enough that he could get off a shot—but he waits. “They’re going to come up one more time,” he says.

Seconds later the whale surfaces, blows once more, and arches its body to dive again. Its body bends and its dorsal fin arches a few inches farther out of the water—like a spring compressing—to propel the animal hundreds of feet down, again. Friedlaender squeezes the trigger. Thunk. The dart strikes just below the dorsal fin and bounces off.

He guides the boat over and scoops the floating dart from the water. A blob of white hangs limply from its hollow end, like a soggy dumpling—a plug of blubber as big around as a pencil, plucked from the whale’s body.

Despite the occasional miss, Friedlaender has this procedure down to a science. He usually waits to shoot, waits for that one last second before the whale dives, when its dorsal fin arches a tiny bit higher, enlarging his target a few inches. He prefers to strike the animal in the same place every time—just below the dorsal fin. It isn’t a matter of perfectionism. It actually improves the quality of the data he collects. In addition to genetic studies, Friedlaender’s team will measure a variety of hormones in the blubber, offering clues to how well the animal is nourished, its health, and its general level of stress. The levels of some hormones in the whale’s blubber actually vary from one part of the animal to another; so hitting the same place every time actually matters.

A photo posted by National Geographic Adventure (@natgeoadventure) on Apr 15, 2016 at 6:36am PDT

A Breath of Fermented Krill

After three hours on the water, Friedlaender has collected half a dozen biopsies, and Bejder and Christiansen have photographed each of these whales from above. We approach a threesome of humpbacks—Friedlaender, crossbow in hand, looking to take one more biopsy. And then comes a memorable moment.

The water erupts just ahead of our boat—a blow of mist. It hovers, drifts in the breeze, dampens our faces, jackets, and hands. My notebook is coated in dew. Then we smell it.

The odor is blunt and pungent, almost a taste in the mouth, an unholy mingling of fart and fishiness—hundreds of gallons of air forcefully expelled from its lungs, laced with the fumes of half-digested krill, hundreds of pounds of these slow-dissolving crustaceans fermenting in its stomach.

One whale after another submerges and resurfaces, exhaling with a growl that evokes thoughts of Jurassic Park—low, guttural, cavernous, with a hint of rubbery, thin-walled vibration.

It’s easy to typecast humpbacks as peaceful grazers, but those growls bring roaring back the fact that they’re indeed predators, among the largest, most efficient predators Earth has ever seen, through their great size having done away with the messier aspects of predation—teeth, claws, blood, and guts. These Imperial Death Stars of the oceans simply open their mouths and quietly engulf entire galaxies of krill. Everything unsightly happens on the inside, in the whale’s belly.

Those growls inspire adrenalin—and also the thankful thought that humpbacks lack the appropriate mouth parts for consuming humans.

The animals glide barely beneath the water, underneath us. They are three times the length of our boat and seem no more than an inch from brushing against us.

Only feet from the boat, one after another rolls in the water like a dog scratching its back on a rug. A pectoral fin as large as a surf board extends from the water, its knobby front edge adorned with barnacles and kelp.

The whales dive and resurface. Their vertical snouts rise four feet from the water. For 10 or 15 minutes they cavort like this, in close contact with our boat. Once as they glide underneath, a whining, vibrational hum emanates from the water around us.

It’s easy to think that this is about us—some form of interspecies communication. And it’s mind blowing to remember that Friedlaender has already stuck two of these animals with biopsy darts, and yet they nuzzle us like cats. But over time the touchy-feely display drifts off to the starboard side of our boat, gradually farther away, like a mindlessly wandering dust devil. And so occurs an equally profound thought: Maybe we’ve just been flies on a wall—utterly unimportant and irrelevant as these animals addressed one another.

Writer Douglas Fox and photographer Carolyn Van Houten spent 15 days aboard the M.V.Ortelius as the ship explores glacial fjords along the Antarctic Peninsula, conducting studies of humpback and minke whales. Follow their story here, then see more about life in Antarctica on the new show Deep Freeze, on the National Geographic Channel in fall 2016.